The invention relates to a medium dispenser. With it media can be distributed or dispensed through a medium outlet. In so doing, the medium can have its final contact with the dispenser at this medium outlet. Such dispensers particularly have a medium or fluid duct, which can be made up of separate ducts such as channels or the like. Contrary to significantly extended medium chambers they can form significantly narrower medium chambers. The other medium chambers can be provided to store the medium, as pressure chambers to generate delivery pressure or the like. They can be connected to a medium duct at their entrance and/or exit. These serve to fill or empty the medium chamber when actuating the dispenser.
Appropriately, the fluid duct is separate from the medium duct. In the event of pressure compensation of a medium chamber the flow can be counter to the medium flow. The fluid, like atmospheric air, flows into the medium chamber, in case the latter has come under low pressure as a result of emptying, temperature change or the like. This supply of the fluid can easily result in microbic contamination of the medium. It is therefore appropriate for such ventilation ducts to run solely via a sterilizing or germ filter or the like in order to make the air throughput germ-free.
Notwithstanding that, however, germs can also penetrate into the device in the area of the medium outlet, possibly into the medium chambers, along the medium duct. This leads to microbic contamination and therefore to the medium being spoilt as well as the dispenser becoming useless. That can be countered by closing means located in the vicinity of the medium outlet. When closed, they are capable of forming a germ barrier.
Consequently, the invention is based on the object of creating a dispenser or delivery device, with which the disadvantages of known designs and respectively of the use either of only a germ barrier at the medium outlet or a germ barrier in the fluid duct are avoided and which, in particular with a simple construction, has very safe combined functions of the barriers.
According to the invention, therefore, shutting blocks or germ barriers are provided as well for the outlet as for the fluid duct. If in order to actuate delivery of the medium the dispenser has two units which can be moved against each other one barrier is appropriately held or displaceably mounted on the one unit and the other barrier on the other unit. By actuating delivery both barriers perform reciprocal motions synchroneously with the actuation.
The medium outlet, particularly an atomizing nozzle, is appropriately formed by means of the outer end of a short nozzle channel. The inner end of which can directly adjoin a conical or similar extension. It appropriately forms the closing surface of the relevant barrier. The closing surface of a movable sealing member can adjoin this closing surface in a closed state. Both closing surfaces appropriately only adjoin each other in a line-shaped and respectively ring-shaped manner. Thus extremely small creepage paths for the germs are achieved. High closing and surface pressures respectively have to be achieved. Despite non-elastically flexible closing surfaces a very tight seal is guaranteed. The nozzle channel, which is bounded to one part and forms the medium outlet with its end, can--as with the sealing member--be extended only once or multiply upstream of the closing surface. Thus the sealing member can be slidingly guided over an axial path of its opening or closing motion directly in this nozzle channel. The faces that slide together, when in a closed position, can form an additional germ barrier. It directly connects upstream to the closing surfaces that abut together axially. It clears passage for the medium only after a first partial path of the opening stroke of the sealing member.
During the closing motion the sealing member, like a pump piston, ejects in a pulsed manner the medium out of the nozzle channel through the medium outlet. Thus the nozzle channel between the end of the sealing plunger and the medium outlet is completely emptied on account of the mass inertia of the medium. The residual medium present there is expelled into the open in an atomized state.
The germ barrier for the fluid duct could be designed in accordance with DE-OS 35 03 354, to which reference is made for inclusion in the application on hand due to further characteristics and effects. Appropriately, this germ barrier can also be designed in keeping with German patent application No. 196 10 457.2, to which detailed reference is made for the same reasons.
Both actuating units that are to be moved against each other are appropriately provided with a anti-pull-off device to further protect against germ penetration. It sufficiently prevents or hinders both units being pulled apart. It is advantageous that a safety member of this safety device is formed by a holder, such as a crimp ring, which envelopes another component or is attached to the latter. The safety device is displaced from the upstream end of this holder. The safety member can lie on the outer circumference of the holder or be effective at a distance from this outer circumference. It can be produced particularly easily if it is formed by bending deformation or by edge-rasing the end of the holder. This is made of a relatively soft, e.g. metallic, material. With the safety device a germ barrier in the joint between the acutating units, e.g. on a plunger ram, cannot be opened by mistake.
It is also advantageous if this holder bounds the fluid duct with its inner circumference. Thus the accompanying germ barrier can lie completely encapsulated within the holder. Fluid inlets can be bounded at a mutual axial distance by the holder. They can be located at one or both ends of the holder within a casing of the actuating unit which has the medium outlet.
With regard to the design of the dispenser or of the respective barrier or of the respective seal, reference is furthermore made to the following documents for inclusion of the characteristics and effects in the application on hand: DE-OS 33 15 334, DE-OS 41 10 302, DE-OS 41 10 304, DE-OS 44 03 755, DE-OS 44 41 263, German patent applications 196 06 701.4, 196 06 702.2, 196 06 703.0, 196 05 153.3 and DE-OS 44 17 488 and DE-OS 44 03 755.
Particularly good atomization as well as very effective emptying of the nozzle channel are achieved if the medium pump, for example a thrust piston pump, is again topped by a second pump stage, in particular a bellows pump. After leaving the medium pump, the medium is once more accelerated in it by contracting the pressure chamber. The pressure chambers of the medium pump and of the additional pump stage are contracted simultaneously. The jacket of the pressure chamber of the pump stage can form a return spring. For example, for the germ barrier or for the seal of the medium outlet. The pressure chamber of this pump stage or the associated end of the return spring can directly or in one part connect to a control plunger for the outlet closure. This results in a very compact construction. These components as well as the holding device for the return spring or the like can be located substantially completely within the outlet stud. Transverse surfaces, provided for actuating the dispenser by manual pressure, protrude over the outer circumference of the upstream end of this stud. The stud is suited for insertion into an opening of the body, such as a nostril.
Besides from the claims, also from the description and the drawings these and further characteristics will be aparent, whereby the individual characteristics, the protection of which is being claimed, can be realised singly or multiply in the form of subcombinations for one version of the invention and in other fields, and can portray versions that are advantageous and in themselves protectable.
The subdivision of the application into individual sections as well as intermediate headings does not restrict the statements made therein in their general validity.